Over the course of time, many different techniques have been implemented in order to teach the proper mechanics of various athletic motions, including swinging a golf club. Many instructors, e.g., golf professionals, use a video analysis system to teach a student how to properly swing a golf club. Using a typical video analysis system, the student's golf swing is captured by a video-recording device. The instructor replays the recorded video information to illustrate the student's golf swing while providing feedback regarding the swing. Instructional feedback may be comments relative to problems associated with the student's swing, compliments regarding improvement in the student's swing, suggestions on correcting the user's swing, or any other verbal instructional comments in context with the student's swing. Visualizing one's personal golf swing in this manner has been recognized as a valuable tool in identifying problems as well as correcting those problems in order to improve the overall golf swing.
Although video analysis systems are widely used by golf professionals, these systems have drawbacks. One drawback relates to having a golf professional subjectively analyze the video information. Not only is this analysis subjective and therefore open to interpretation and subject to inaccuracies, but also such analysis is exacerbated by the fact that many problems associated with a golf swing are typically not captured by the video recording system given different camera angles, too few cameras, or loose clothing. Therefore, golf professionals are typically forced to guess the problem. Accordingly, the advice given by a golf professional may be inaccurate and inconsistent since it is difficult to isolate mechanics and measurements of the swing on video.
In order to overcome the drawbacks associated with typical video analysis systems, instructors have adopted motion or position analysis systems as an aid to analysis and instruction. Since the 1970's, universities and private research foundations have studied human motion using techniques that allow two-dimensional film or videotape to be processed into three-dimensional data. Progress had been made in characterizing the properties of human motion (biomechanics) from the simple measurements of displacement, velocity, and acceleration to the more complicated measurements of force and torque (stress). Although the scientific community has taken steps towards understanding human motion and its effects upon the musculosketal system, very little of this information has been applied to the clinical area where a patient can directly benefit.
Current motion analysis systems require that the student/athlete to wear sensor elements on their body and the sensor elements transmit positional data of isolated body parts, such as hands, hips, shoulders and head. The isolated points on the body are measured during a swing in accordance with an absolute reference system, e.g., a Cartesian coordinate system wherein the center point is a fixed point in the room. By using motion analysis, exact measurements are provided from which an instructor can more accurately determine problems in a student's swing. Even though motion analysis provides accurate positional data of the student's swing, it is not, in and of itself, particularly useful since it gives no visual aid as to where the problems may really be. When used by itself, the motion analysis system is not an effective teaching tool since the instructor is only provided with numbers and not a visualization of what the student is doing wrong. Some motion analysis systems provide animation that depicts elements of a golf swing based upon captured data. However, the animation is crude and doesn't show the golfer what he/she looks like during a swing.
Consequently, motion analysis systems are used with video analysis systems in order to try to overcome the problems associated with each system as it is used independently of the other. The instructor may use the motion capture data and subjectively map the information to the video data. Although this provides more specific data to the instructor, it is associated with at least one significant problem. The instructor, while viewing the video, must estimate the swing positions corresponding to the data points from the motion analysis information. Analysis of the swing requires not only considerable effort, but also a significant amount of estimation in associating the positional data points with an associated position on the student's swing.
Moreover, the systems for providing the video analysis are separate from the systems that provide motion capture information such that the instructor must manipulate numerous controls for displaying, to the student, the various positional measurement values as well as for providing separate video replays.
With respect to golf and the golf swing, some systems have been developed to respond to the needs of both the self-taught player and the professionally taught player. Examples of such systems are: (1) the Sportech Golf Swing Analyzer and WAVI.TM. system both manufactured by Sports Technology, Inc. of Essex, Conn.; (2) BioVision.TM. manufactured by Optimum Human Performance Centers, Inc. of Menlo Park, Calif.; (3) the Pro Grafix System manufactured by GolfTek of Lewiston, Id.; and (4) the Swing Motion Trainer manufactured by Sport Sense of Mountain View, Calif.
Other prior art teaches, for example, a system where a golfer wears a number of reflective tapes at various places on his or her body. While the player swings the club, a TV camera captures the motion of the golfer through the motion of the reflective tape. The image of the motion is digitized and the two-dimensional coordinates of the reflective tapes are calculated. The calculated coordinates are then manipulated in various ways to analyze the golfer's swing. For example, the coordinates can be used to construct a moving stick figure representing the golfer's swing.
Another system discloses a video device and method which detects the club head velocity via a colored club head and color detection unit. The club head velocity is then displayed in analog or digital form. A series of swings can then be analyzed by comparing the relative club head velocities for different club swings.
Yet another system provides a video system which displays a live video signal of a golfer's swinging motion for the golfer to see while swinging. A series of video overlays can be imposed upon the video signal for reference and analysis purposes.
There is an apparatus and method which uses a computer to produce a series of still images from a videotape of a golfer's swing. The still images are then overlaid with a series of corrected images which include lines depicting proper form. The result is then augmented with further visual or audio information and recorded onto another tape for viewing and analysis.
A golf practice apparatus provides recording and instant playback of video images of a golfer's swing. An infrared camera and flash unit are used to obtain snapshot images of the clubhead and ball just before and after impact. An optical sensor array and processor calculates statistical data on club speed, ball speed, and ball angle.
What is lacking in the field is an athletic motion analysis apparatus and method which is capable of capturing and plotting the total motion of a user with sufficient data to reduce, analyze, report on, and present the component parts of the motion and the degree of coordination of the component parts as feedback to the user in such a way as to optimize his assimilation and understanding of the information; further to provide a comparative study of the component parts of the user's performance as to its own prior test results or the performance of other persons or other benchmark values; and further, to provide a related prescription of specific exercises tailored to the user's level of performance, areas of deficiency, and available time for improving his or her skill level through practice of training exercises.
For example, as a golf swing is executed, the golfer rotates, among other things, the hips, shoulders, and arms in a sequential, and yet coordinated fashion. To maximize energy in the swing, the golfer must smoothly transfer energy from the feet to the hips, to the shoulders, to the arms, and hence to the club, culminating at the time and point of impact with the ball. What is needed is a system and method of motion capture and data processing with specialized software to process this data and generate a coordinated, multiple format presentation to the user which will effectively demonstrate the most efficient kinetic link between the golfer's motion segments, and prescribe exercises likely to improve the user's performance.
It is with respect to these and other considerations that the present invention has been made.